The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A231295 Number of (n+1) X (1+1) 0..2 arrays with no element unequal to a strict majority of its horizontal, vertical and antidiagonal neighbors, with values 0..2 introduced in row major order. 1
1, 2, 4, 12, 32, 92, 264, 756, 2176, 6252, 17976, 51684, 148592, 427228, 1228328, 3531604, 10153824, 29193548, 83935256, 241324740, 693839952, 1994879932, 5735538696, 16490418228, 47412092736, 136315920428, 391925964280 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) + 3*a(n-2) - 4*a(n-4).
Empirical g.f.: x*(1 + x)^2*(1 - 2*x) / ((1 - x)*(1 - x - 4*x^2 - 4*x^3)). - Colin Barker, Sep 28 2018
EXAMPLE
Some solutions for n=4:
..0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0....0..0
..0..0....0..0....0..1....0..1....0..1....0..0....0..0....0..0....0..0....0..0
..0..1....1..1....1..1....1..1....1..1....0..0....1..1....1..1....0..0....0..0
..1..1....1..1....0..0....2..2....1..1....0..1....1..2....1..0....1..1....0..0
..1..1....1..1....0..0....2..2....1..1....1..1....2..2....0..0....1..1....0..0
CROSSREFS
Column 1 of A231302.
Sequence in context: A152035 A026151 A025178 * A087211 A161177 A039721
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 07 2013
STATUS
approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 19 13:25 EDT 2024. Contains 372694 sequences. (Running on oeis4.)